<?php
/**
 * This file houses the TimeFilter class.
 * 
 * Copyright (c) 2010, Kalkomey Enterprises, Inc.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * - Redistributions of source code must retain the above copyright notice, this list
 *   of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice, this 
 *   list of conditions and the following disclaimer in the documentation and/or other
 *   materials provided with the distribution.
 * - Neither the name of the Kalkomey Enterprises, Inc. nor the names of its 
 *   contributors may be used to endorse or promote products derived from this 
 *   software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * @license http://www.opensource.org/licenses/bsd-license.php New BSD License
 * @copyright Copyright (c) 2010, Kalkomey Enterprises, Inc.
 * @link http://code.google.com/p/swerv/
 * @package	Framework
 * @subpackage Filters
 */

/**
 * The TimeFilter class ensures that the property in the model is a properly formatted time.  Validates time as 24hr (HH:MM) or am/pm ([H]H:MM[a|p]m).
 *
 * @package	Framework
 * @subpackage Filters
 */
class TimeFilter extends Filter
{
	
	/**
	 * Object constructor.
	 *
	 * @param string $errorMessage the error message to return if this property fails validation
	 *
	 * @return NotEmptyFilter
	 */
	public function __construct($errorMessage)
	{
		$this->errorMessage = $errorMessage;
	}
	
	/**
	 * Checks the provided value and returns either null (if the value is valid) or a string (the error message).
	 *
	 * @param mixed $value
	 *
	 * @return null|string
	 */
	public function Check($value)
	{
		$returnValue = null;
		$regex = '%^((0?[1-9]|1[012])(:[0-5]\d){0,2}([AP]M|[ap]m))$|^([01]\d|2[0-3])(:[0-5]\d){0,2}$%';
		if (!preg_match($regex, $value))
		{
			$returnValue = $this->errorMessage;
		}
		return $returnValue;
	}
	
}

?>